AJay Jadhav

S12XS: Data Register vs Input Register

Discussion created by AJay Jadhav on Dec 20, 2007
Latest reply on Dec 20, 2007 by Steve Mcaslan
We can read the pin state either from Port data register ( PTT, PTS,PTM,PTP,PTH,PTJ) or corresponding port input register ( PTIT, PTIS, PTIM, PTIP, PTIH, PTIJ).
Is reading from port input register prefferable than port data register, why?
Also for Ports A,B,C,D,E,K ( which are General purpose I/O registers) we need to read from port data register only.
So am I correct if I write to ports using data registers and read from port input registers?